The uncertainty of detecting planets
(PHYSorg.com Space & Earth)

Uncertainty in science is a good thing. Because here`s how the scientific model works: you observe a phenomenon, then form a hypothesis about why that phenomenon is taking place, then test the hypothesis, which leads you to develop a new hypothesis, and so on. That process means it can be difficult to ever definitely know something. Instead, scientists work to understand the uncertainty in their measurements, their models, their conclusions.